<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>file_up</title>
</head>
<body>
<form method="post" enctype="multipart/form-data">
    <label>头像</label>
    <input name="avatar" type="file">
    <br>
    <label>提交</label>
    <input type="submit" value="提交">
</form>
</body>
</html>